Spiral sewing attachment for sewing machines



INVENTORS.

ITORNEY.

2 Sheets-Sheet l SAM DESPERAK JOSEPH ROSCHKO GERARD DESMOND BY THEIR AMarch 6, 1956 s. DESPERAK ETAL SPIRAL SEWING ATTACHMENT FOR SEWINGMACHINES Filed July 16, 1953 March 6, 1956 s. DESPERAK ET AL 2,737,133

SPIRAL SEWING ATTACHMENT FOR SEWING MACHINES Filed July 16, 1953 2Sheets-Sheet 2 INVENTORS.

S A M DESPERAK JOSEPH ROSCHKO GERARD DESMOND BY QZM THEIR ATTORNEY.

United States Patent SPIRAL SEWING ATTACHMENT non SEWING MACHINES SamDesperak and JosephRoschko, Brooklyn, and Gerard Desmond, Franklin.Square, N. Y.

ApplicationJuly 16, 1953, Serial No. 368,372

4 Claims. (Cl.i112-2) This invention relates'to a spiral sewingattachment for sewing machines and it constitutes an improvement overthe spiral stitching attachment which is disclosed and claimed in ourco-pending patent application Serial when of a fragile nature tends tobecome distorted and to tear and the spiral stitching also becomesdistorted. Said attachment occupies a relatively large space on thesewing machine table.

The spiral sewing attachment herein claimed affords many advantages overour earlier spiral stitching attachments described in said co-pendingpatent application and consequently the present spiral sewing attachmentconstitutes a marked and very substantial improvement over the priorart. 7

In the present device, the work is-moved in a straight path toward andaway from the sewing machine needle. There is only one cam in thepresent attachment and that is the cam which engages and actuates thework supporting means. The work supporting meansis simply a bar which ismounted for movement-longitudinally of itself in either direction, thatis, both toward and away from the sewing machine needle. The cam whichactuatessaid bar may be of the closed cam track top in which case thecam would not only thrust or propel the work supporting bar inoutward'directionbut it-would also. pull or draw said work supportingbar in inward direction. The cam may, however, have only a single camface along its outer edge, in which case it'would serve only to push orthrust the work supporting-bar away from it. A spring would be employedto maintain the bar in engagement with said cam face and to urge it inthe direction of said cam when the cam tends to release it.

An important feature of the present attachment, as of the earlierpatent, is the clutch mechanism whereby the-work supporting means may bestopped from moving at any stage of the operation of the attachment andwhereby it may be moved to any selected position along its normal pathof movement. Consequently, at the conclusion of one spiral stitchingoperation the attachment may be returned to its starting positionpreparatory to engaging in the next spiral stitching operation.Similarly, should the thread happen to break during the course of aspiral stitching operation, the attachment may be returned to theposition whichit occupiedat the precise moment that the thread broke sothat the stitching operation may. resume from that point on without anyoutward evidence of an interruption or breakirr the stitching.

The invention is illustrated in the accompanying drawing in which:

Fig. 1- is aplan view of a spiral sewing attachment made in accordancewith the present invention.

Fig. '2 is a fragmentary plan view showing a different type of cammechanism for use in the same attachment which is shown in Fig. 1.

Fig. 3 is a fragmentary side view of the attachment shown in Fig. 1.

Fig. 4 is another fragmentary side view thereof, showing the workholding means, including the means for holding the work down upon saidwork holding means.

Fig. 5 is a view of the underside of the cam mechanism and clutchmechanism looking in the direction of arrows 5,5 of Fig. 3.

Fig. 6 is a somewhat schematic plan view showing a work piece on thework holder.

The attachment herein claimed includes a base plate '10 which is mountedon a sewing machine table 12. It maybe set into said sewing machinetable so'that' the work 14 will be supported on a common plane with theoperative surface of the table top. 'U-shaped brackets '16- and 18 aresecured to base plate 10 by means of screws 20 or other fastening means.Slidably supported onbase plate 10 and under brackets 16 and 18 is abar22- which may be described as the work supporting bar of the attachmentherein claimed. At the forward end of work supporting bar 22 is a pin 24which projects and points upwardly. It is on this pin that work 14 maybe impaled; To hold the work on the work supporting bar 22 and toprevent it from disengaging pin 32 to work supporting bar 22.

It will be observed that a button 36 is provided below block 28- and forengagement therewith. This button is urged upwardly by means ofcompression spring 38. There is sufiicient friction between spring-urgedbutton 36and block 28'to hold rod 26 in any selected angular positionabout=the axis of screw 30. It will be observed that block 28 isprovided witha rounded corner 40 at itsback end. This rounded cornerwill allow block 23 to pivot about screw 30 although said block iscontinuously engaged by button 36. 'At the forward end of rod 26 is ahole 42 which is formed in said rod axially there When the workisimpaled'on pin- 24, rod 26 may be pivoted inclockwise direction asviewed in Fig. 4 to the position which it is shown to occupy in saidFig. 4.

The spring tension'which button 36-exerts upon block 28 will tend tohold rod 26 in its sai'd'Fig. 4 poistion and-in-suh position said rodwill prevent, displacement of the -'work from the work supporting pin24;

It-will-be observed at this point that an arcuate' plate 44 is-mountedon the forwardlyextendingportion or arm of -rod- 26: When the work isrotated on pin 24 during the spiral stitching operation, it tendstofoldfup wardly and upon itself and this arcuate plate 44" engages theworkandpreventssuch folding. ltwill 'be observed that a spring wire-'46is secured at its upper end by means of screw 48' to the sewing machinehead 50. At the lower endofwire 46' is a shoe 52 which is situated infront of the sewing machine needle 54. Shoe 52 engages the work as thework is fed'to the sewing machine needle and said shoe smoothes the'workand helps feed it smoothly and uniformly to the, needle. 7

It will be understood that work supporting bar '22 is 22 away from saidsewing machine needle will now be described.

Cam 62 is pivotally mounted on a vertical shaft 64 for angular movementon a horizontal plane. An arcuate cam track 66 is formed in cam 62. Acam follower 68 is mounted on bar 22 for engagement with said cam track66. Cam follower 68 may be a roller having a diameter which is butslightly smaller than the width of cam track 66. It will be understoodthat when cam 62 is caused to turn in one direction about the verticalaxis of shaft 64, the engagement of cam follower 68 with cam track 66will cause bar 22 to move in one longitudinal direction. When cam 62 iscaused to turn in the opposite direction on shaft 64, bar 22 will becaused to move longitudinally in the opposite direction.

A variation of this cam arrangement is shown in Fig. 2 where a cam 70 isprovided which is adapted to be used as a substitute for cam 62. Thiscam 70 does not have a cam slot or track corresponding to cam slot ortrack 66 in cam 62. Instead, it is provided with a cam face 72 along itsperipheral edge and it is said cam face which cam follower 68 engages.An extension spring 74 is secured at one end by means of screw 76 to bar22 and it may be secured at its opposite end by means of screw 78 to cam70. The action of this spring is to hold cam follower 68 in engagementwith cam face 72 of cam 70. It also functions as the means of pullingbar 22 longitudinally in one direction away from the sewing machineneedle. Cam 70 serves only to push said bar 22 in the oppositelongitudinal direction, that is, in the direction of said sewing machineneedle. It will be understood that although spring 74 is shown to beattached at one end to cam 70, this is purely illustrative as it mayequally as well be attached to a fixed part of the attachment, such asthe base plate 10.

Shaft 64 is suitably supported in vertical position for rotary movementabout its own longitudinal axis. At its lower end is a bevel gear 86which is engaged by a second bevel gear 82. The latter gear is securedto a horizontal shaft 84 on which a pulley 86 is mounted. A drive belt88 engages pulley 86 and suitable means, including a speed reductiongear box and the motor drive mechanism of the sewing machine, operatethrough said belt 88 to cause said pulley and said bevel gear wheels andshaft 64 to rotate. Actually, the speed of rotation of shaft 64 is suchthat the work will rotate any number of times, say as many as ten orfifteen or twenty times or more for each revolution of shaft 64.

Although cam 62 is mounted on shaft 64, it is not fixed to said shaftand it is possible, as will hereinafter be seen, for said cam and saidshaft to move relatively to each other either in the same angulardirection or in opposite angular directions. A disc-shaped member 90having a hub or collar 92 is secured to shaft 64, either by means of pinor set screw 94 or by any other suitable and conventional means. Disc 90always rotates with shaft 64 in the same angular direction. Aring-shaped bead or raised portion 96 is formed on disc 90 peripherallythereof. Engageable with said bead 90 is an arm 98 and more particularlygroove 100 formed in said arm 98. Arm 98 is mounted at one end on cam 62by means of screw 102 or by any other suitable means. An expansionspring 104 is secured at one end to the opposite end of arm 98 and saidspring is secured at its opposite end to a pin 106 which is secured tocam 62. There are several such pins 106 and they are all disposedvertically at equally spaced intervals from each other and from theaxial center of shaft 64. It will be noted particularly in Fig. 5 thatpins 106 engage bead 96 of disc 90. In other words, these pins 106 serveas bearings between cam 62 and the peripheral bead 96 of disc 90.

Slot 100 may be an arcuate slot situated and oriented in such manner onarm 98 as to enter into concentric relation to bead 96 when arm 98 is inone position and into eccentric relation to said bead 96 when arm 98 isin another position. Spring 104 acts upon arm 98 to swing it to its lastmentioned position wherein slot 100 is eccentric relative to bead 96.When arm 98 is in this position, the walls and corners of slot 100engage bead 96 and any angular movement of disc thereby causes angularmovement of arm 98 and cam 62 to which said arm is attached. The camwill now move integrally with said disc 90. When it is desired to stopthe cam or to move it relative to disc 90, all that need be done is toswing arm 98 to its first mentioned angular position wherein its slotenters into concentric relation to bead 96. There is no longer anylocking or gripping action between said arm 98 and said bead 96 andconsequently arm 98 and cam 62 are free either to stop or to moverelative to disc 90. This movement of arm 98 to a position wherein itsslot is concentric with bead 96 takes place against the action of spring104.

It will be noted that a second arm 108 is provided on cam 62. Thissecond arm is pivotally mounted at one end on shaft 64. At its oppositeend it is provided with a handle 110 which extends vertically upwardlythere from. A second handle 112, also extending vertically upwardly, issecured to cam 62 a spaced distance from handle 110. By squeezing thetwo handles together, that is, by moving handle 110 in the direction ofhandle 112, arm 108 may be moved in clockwise direction as viewed inFig. 1. It will be noted that a notch 114 is formed along one edge ofarm 108 and said notch is engageable with a pin 116 on arm 98. As viewedin Fig. 1, spring 104 acts upon arm 98 to cause it to swing in clockwisedirection and into engagement with notch 114 on arm 108, thereby causingsaid arm 108 to move in counterclockwise direction as far as it ispermitted to go in that direction. When the two handles 110 and 112 aresqueezed together, arm 108 will be moved in clockwise direction againstpin 116 and against the action of spring 104. Arm 98 will accordingly becaused to move in counterclockwise direction to bring its arcuate slot100 into concentric relation with bead 96, thereby releasing said beadand freeing cam 62 for angular movement rel ative to disc 90 or for nomovement whatsoever although disc 90 continues to rotate.

It will be observed that cam 62 is now free to be moved manually to anydesired position as, for example, its starting position or to a positionat which the sewing machine thread happened to break. Thus far nothinghas been said regarding the stopping of shaft 64 and of the drivemechanism connected thereto. It will be seen in Fig. 1 that an arm 118projects laterally horizontally from bar 22. Adjustably secured to arm118, by means of screws 120, is a wire loop 122 which is closed at bothends. This wire loop may, when screws 120 are loosened, be movedlongitudinally of bar 22 in either direction. Screws 120 may betightened to lock said wire member 122 in any selected position on arm118. It will be observed that a wire arm 124 projects laterallyoutwardly from the back end of wire loop 122. This wire arm 124 isengageable with switch arm 126 of a normally open microswitch 128. Whenbar 22 is moved rearwardly to its dotted line position in Fig. 1, wirearm 124 will engage switch arm 126 and will actuate said switch arm toclose the switch. This switch is connected to the circuit whichenergizes the solenoid which controls the sewing machine clutch.Consequently, when switch 128 closes, the circuit to said solenoid willbe made and the solenoid will be energized. This will disengage theclutch which connects the sewing machine to the sewing machine motor andthe sewing machine will accordingly stop. Since the drive mechanism ofthe attachment herein disclosed and claimed is also connected to thesame drive mechanism which operates the sewing machine, the closing ofswitch 123 will cause the attachment herein claimed to stop.

The foregoing illustrates preferred forms of this invention and it willbe understood that the spirit of the invention and the scope of theclaims are sufficiently broad to encompass variations in the disclosedforms of this invention and also other forms as well. For example, whencam 62 turns in clockwise direction as viewed in Fig. 1, bar 22 will bedrawn downwardly away from the needle, also as viewed in said Fig. 1. Itwill be understood that the cam may be so oriented that it will draw thebar away from the needle when the cam turns in counter-clockwisedirection. Other variations are of course within the purview of thepresent invention.

We claim:

l. A spiral sewing attachment for sewing machines having a drivemechanism operating a work feed and a needle, comprising a horizontalbase plate adapted to be mounted on a sewing machine adjacent the workfeed and needle, parallel guides mounted on said base plate, a worksupport slidably mounted between said guides with its front end facingsaid needle for movement in parallel relation to said guides, saidguides being oriented on said base plate relative to said needle toguide said work support in a horizontal straight line toward and awayfrom said needle laterally of the path of feed of the Work feed, a camplate disposed on a horizontal plane above said base plate and adjacentthe back end of said work support, said cam plate being angularlymovable about a vertical axis and having a vertically disposed cam faceformed thereon, a cam follower being provided on the work support inengagement with said cam face, whereby angular movement of said camplate about its vertical axis causes the work support to move in astraight line between said guides in one direction relative to theneedle, a rotary drive mechanism adapted to be operatively connected tothe sewing machine drive mechanism, and a disengageable clutch connectedbetween said rotary drive mechanism and said cam plate below the camplate, operable means extending through the cam plate and connected tothe clutch to engage the clutch and cause the cam plate to engage inangular movement about its said axis, and to disengage the clutch andfree the cam plate from engaging in angular movement and thereby to stopthe straight line movement of the work support.

2. A spiral sewing attachment in accordance with claim 1, wherein thecam plate has a cam slot formed therein for said cam follower, saidvertical cam face being provided on one side of said cam slot and asecond vertical cam face being formed on the opposite side of said camslot, said cam faces being parallel to each other, whereby angularmovement of said cam plate in one direction about its said vertical axiscauses one of said cam faces to engage the cam follower and to push saidcam follower together with the work support on which it is mounted inone straight line direction relative to the sewing machine needle, andwhereby angular movement of said cam plate in the opposite angulardirection causes the other cam face to engage the cam follower andthereby to pull said cam follower together with said work support in theopposite straight line direction relative to said sewing machine needle.

3. A spiral sewing attachment in accordance with claim L'Wherein aspring is connected between the work support and the cam plate to urgethe work support in the direction of the cam plate and thereby tomaintain said cam follower in engagement with said cam face, wherebyangular movement of the cam plate in one direction about its said axiscauses the cam follower and work support to move in one straight linedirection relative to the sewing machine needle and against the actionof the spring, and whereby angular movement of the cam plate in theopposite direction about said axis enables the cam follower and worksupport to move in the opposite straight line direction relative to saidsewing machine needle in response to the action of said spring.

4. A spiral sewing attachment in accordance with claim 1, wherein thecam plate is mounted for angular movement in either direction about itssaid vertical axis and wherein the rotary drive mechanism is adapted torotate in only one direction, said clutch comprising a rotatably mounteddisc which is connected to said rotary drive mechanism for rotarymovement therewith in a common direction, and a locking arm which ispivotally secured to said cam plate, said disc having an annular beadformed thereon and said locking arm having a slot formed therein whichaccommodates said bead, said bead being eccentric with respect to thepivotal axis of said locking arm, the side walls of said slot in thelocking arm being thereby engageable with said head to lock the lockingarm and disc against relative movement when said locking arm is in oneangular position about its said axis relative to the bead so as to causethe cam plate to move integrally with said disc when the disc engages inrotary movement with the rotary drive mechanism, said side walls of theslot being disengageable from said bead by said operable means connectedto the clutch to free the locking arm and disc for relative movementwhen the locking arm is moved to another angular position about its saidaxis relative to the bead, thereby freeing the cam plate from the discand enabling the cam plate to stop or move relative to the disc althoughthe disc continues to engage in rotary movement with the rotary drivemechanism.

References Cited in the file of this patent UNITED STATES PATENTS1,462,168 Denemark July 17, 1923 1,909,138 Vollmer May 16, 19332,086,835 Adkisson et a1 July 13, 1937 2,437,624 Sutker Mar. 9, 19482,551,261 Gensheimer May 1, 1951 2,674,963 Guide Apr. 13, 1954

